From DE 697 03 622 T2 a device for a wind turbine is known that is provided for the transmission and damping of yaw movements, wherein the device comprises a yaw bearing and a yaw movement rotational drive that permit a rotation of the machine installation about a vertical axis as well as a drive device for driving the machine installation about a vertical axis. In addition, a coupling is provided to transmit the torque of the drive device to the yaw movement rotational drive and is arranged so that the torque transmitted by the coupling is determined by the difference of the rotational movement speed of the drive shaft and output shaft of the coupling. The drive device has a brake, an electric motor that can be blocked by the brake and a gear mechanism coupled to the electric motor by interconnection of the coupling.
When the brake is in the locked position, a yaw movement produced by wind is damped by the coupling. In addition yaw brakes may be provided by means of which a yaw movement can be blocked. A blocking of the yaw movement is desired for example for safety reasons when maintenance staff are working on the machine installation and/or in the region of the machine support.
Conventional yaw brakes are arranged on the supporting structure and machine support interface, in particular on or in the region of the yaw bearing. Since the braking forces to be applied by the yaw brakes are large, the yaw brakes are designed correspondingly robustly, which is associated with not inconsiderable costs.